The present invention relates to a system for sharing objects of a plurality of contents (various video contents, various audio contents, and the like).
Also, the present invention relates to an information medium having management data for sharing objects of a plurality of contents, an apparatus for playing back information recorded on the medium, a method of recording information containing the management data on the medium, and a method of playing back information from the medium on the basis of the management data.
As optical discs that can record video (moving picture) data with high quality and at high density, and can record various kinds of information such as multiangle video data, sub-picture data, multilingual audio data, multichannel audio data, and the like, DVD video discs have been developed, and are beginning to be put into the market (DVD is an abbreviation for a digital versatile disc).
The DVD video disc standards can support compressed multichannel audio (AC-3, MPEG, and the like) and non-compressed linear PCM (from a sampling rate of 48kHz/16 quantization bits to a sampling rate of 96 kHz/24 quantization bits). Linear PCM of DVD video has high-sound quality specifications with high sampling rate and high quantization bits superior to conventional music CDs (a sampling rate of 44.1 kHz/16 quantization bits). Especially, linear PCM having a sampling rate of 96 kHz/20 to 24 quantization bits qualifies for the next generation digital audio discs (so-called super CDs or super audio discs).
However, DVD video specifications give priority to video over audio, and audio priority specifications superior to audio specifications of DVD video in terms of not only the sampling frequency and the number of quantization bits but also the number of recordable channels, recordable time, and the like, are yet to come.
To meet such demand, DVD audio specifications are being explored (however, the DVD audio specifications are not yet a prior art). The DVD audio specifications can support up to linear PCM having a sampling rate of 192 kHz and 24 quantization bits as well as linear PCM having a sampling rate of 48 kHz to 96 kHz and 16 to 24 quantization bits. In the future version up of DVD audio specifications, higher-sound quality specifications may be introduced.
DVD audio can cope with such future scale-up since it can commonly use some specifications of DVD video capable of large-amount recording that includes even digital Hi-Vision video as a target.
Also, DVD audio can take future technical, market, and economic advantages that will become available along with the improvement of DVD video.
For example, when a large-amount DVD disc which will be available in the future in DVD video is used in DVD audio, the sampling frequency, the number of quantization bits, the number of recording channels, and the like used in recording can be increased considerably if the recording time remains the same. The technique of a DVD video recorder which will be put into the market in the near future and uses a DVD-RAM (or rewritable DVD-RW or write-once DVD-R) can be used in a DVD audio recorder that will become available soon.
Furthermore, if the market scale expands as DVD video prevails, media (DVD-ROM discs, DVD-RAM/DVD-RW discs, DVD-R discs, and the like), components (disc drive, optical pickup, various ICs, and the like), various control programs, and the like are standardized, and a cost reduction of DVD audio products having many features and high sound quality is promoted. With the spread of DVD audio, DVD video can also take future technical, market, and economical advantages that will become available along with the improvement of DVD audio.
As a management method for controlling playback of video (moving picture) or audio (music or the like) contents, it is a common practice to manage playback of contents produced according to their purposes. By contrast, with recent diversification of users"" requirements, video and music have vague boundary, and requirements for partly using the contents that can be independently played back as video in music or for commonly using contents by allowing video created for music to be played back as video alone are increasing among producers of these contents (contents providers).
The DVD audio specifications according to the present invention can meet such requirements of the contents providers. More specifically, the DVD audio specifications normally give priority to audio over video, but it is possible to build a system compatible with both DVD video and DVD audio. That is, the DVD audio specifications can provide an audio only disc (A disc) including DVD audio contents alone, and an audio+video disc (AV disc) including both audio and video contents. In such case, upon playing back the audio contents of an AV disc, its video contents can also be accessed.
In the DVD audio specifications according to the present invention, not only video picture data as subsets of the DVD video specifications, but also high-resolution still picture data, text information, and menu data (visual menu data that can be freely designed by the contents provider) can be added to audio data with high-sound quality specifications.
It is the first object of the present invention to provide a digital information medium which can access not only DVD audio information but also part (e.g., some video data) of DVD video information in the aforementioned DVD audio specifications.
It is the second object of the present invention to provide an apparatus for playing back information from the digital information medium.
It is the third object of the present invention to provide a method of recording information on the digital information medium.
It is the fourth object of the present invention to provide a method of playing back information from the digital information medium.
In order to achieve the first object, in a digital information medium according to the present invention, first and second contents (ATS, VTS) for different purposes are recorded on a plurality of independent areas (DVD audio zone, DVD video zone). The first and second contents (ATS, VTS) respectively have first and second management blocks (AMG, VMG) to manage playback of their contents. The first management block (AMG) has first information (AMGI) for managing accesses to both the first contents (ATS) and second contents (VTS).
In the medium of the first object, the second management block (VMG) may have second information (VMGI) for managing accesses to the second contents (VTS).
In the medium of the first object, the first management block (AMG) has physically or logically smaller address numbers than the second management block (VMG) or the second contents (VTS).
In the medium of the first object, the first contents (ATS#1) may include information (link information) for accessing the second contents (VTS).
In the medium of the first object, files of recorded information may be managed by a hierarchical file structure including the following sub-directories and root directory. That is, recorded information files can be managed by: a first sub-directory (ATS directory) including a data file (ATS_01_0.AOB) for storing the first contents (ATS) and a data file (AUDIO_TS.IFO) for storing the first information (AMGI); a second sub-directory (VTS directory) including a data file (VTS_01_1.VOB) for storing the second contents (VTS) and a data file (VIDEO_TS.IFO) for storing the second information (VMGI); and a root directory containing the first sub-directory (ATS directory) and the second sub-directory (VTS directory).
In the medium of the first object, the data file (ATS_01_0.AOB) in the first directory (ATS directory) may be formed by objects (AOTT) which contain at least audio data but do not contain video data); and the data file (VTS_01_1.VOB) in the second sub-directory (VTS directory) may be formed by objects (VTS) which contain video data.
In the medium of the first object, the first information (AMGI) may contain first search information (ATT_SRP for AOTT) for accessing the objects (AOTT) which contain audio data but do not contain any video data, and second search information (ATT_SRP for AVTT) for accessing the objects (VTS) containing video data.
In the medium of the first object, the second information (VMGI) may contain search information (ATT_SRP for AVTT) for accessing only the objects (VTS) containing video data.
In order to achieve the first object, an optical disc according to the present invention has a lead-in area (27) at the center, and a volume space (28) and lead-out area (26) in turn around the lead-in area; the volume space (28) contains an audio zone (71) and then a video zone (72); the audio zone (71) contains audio management information (AMG) and audio contents (ATS); and the video zone (72) contains video management information (VMG) and video contents (VTS). In this optical disc, the audio contents (ATS) and video contents (VTS) can contain data cells (VTS_C#2 and the like) which are commonly managed by the audio management information (AMG).
In the optical disc of the first object, the video contents (VTS) can contain data cells (VTS_C#2 and the like) managed by the video management information (VMG), and each of the data cells (VTS_C#2 and the like) managed by the audio management information (AMG) or video management information (VMG) can be formed by a set of data packs each having a predetermined size (2,048 bytes).
Furthermore, in order to achieve the first object, another optical disc according to the present invention has a lead-in area (27) at the center, and a volume space (28) and lead-out area (26) in turn around the lead-in area; the volume space (28) contains an audio zone (71) and then a video zone (72); the audio zone (71) contains audio management information (AMG) and audio contents (ATS); and the video zone (72) contains video management information (VMG) and video contents (VTS). In this optical disc, the audio contents (ATS) contain one or more data cells (audio cell, picture cell, silent cell) managed by the audio management information (AMG), and each data cell (audio cell, picture cell, silent cell) is formed by a set of one or more data packs (A_PCK, SPCT_PCK, and the like) each having a predetermined size (2,048 bytes).
In the other optical disc of the first object, at least one data cell (audio cell) can be formed by packs (A_PCK) of audio information.
In the other optical disc of the first object, at least one data cell (silent cell) can be formed by packs (A_PCK) of audio information consisting of silent information.
In the other optical disc of the first object, the audio contents (ATS) may contain audio title set information (ATSI) for managing its contents, the audio title set information (ATSI) may contain program chain information (ATS_PGCI in ATS_PGCIT) for managing one or more programs (PG#) that form the audio contents (ATS), and the program chain information (ATS_PGCI) may contain information (ATS_C_SA, ATS_C_EA in FIG. 28) indicating the recorded positions of the data cells (audio cell, picture cell, silent cell).
In the other optical disc of the first object, the audio contents (ATS) can contain an audio title set (ATT or AVTT) which includes information pertaining to both audio and video, and an audio only title set (AOTT) which includes information pertaining to only audio.
In the other optical disc of the first object, the audio management information (AMG) can contain information (ATT_SRPT in FIG. 20, the location of which is specified by ATT_SRPT_SA in AMGI_MAT in FIG. 18) of a search pointer (ATT_SRP) for accessing the audio title set (ATT).
In the other optical disc of the first object, the audio management information (AMG) can contain information (AOTT_SRPT in FIG. 20, the location of which is specified by AOTT_SRPT_SA in AMGI_MAT in FIG. 18) of a search pointer (AOTT_SRP) for accessing the audio only title set (AOTT).
In the other optical disc of the first object, the audio contents (ATS) can contain audio data (AOTT_AOB) digitally converted by a predetermined sampling frequency (e.g., 192 kHz) selected from a plurality of different sampling frequencies (48 kHz, 96 kHz, 192 kHz, and the like) and a predetermined number of quantization bits (e.g., 20 bits) selected from a plurality of different numbers of quantization bits (16 bits, 20 bits, 24 bits, and the like), and attribute information (AOTT_AOB_ATR in FIG. 25 included in ATSI in FIG. 24) indicating the predetermined sampling frequency (e.g., 192 kHz) and the predetermined number of quantization bits (e.g., 20 bits) used for this audio data (AOTT_AOB).
In order to achieve the second object, a playback apparatus according to the present invention has an audio management block (AMG) for managing audio contents (ATS) and their playback, and a video management block (VMG) for managing video contents (VTS) and their playback, the audio management block (AMG) plays back the audio contents (ATS) or video contents (VTS) from a digital information medium (AV disc 10) containing audio management information (AMGI) for managing accesses to the audio contents (ATS) and video contents (VTS). This playback apparatus comprises: management information extraction means (30, 50 to 54) for extracting contents (ATT_SRP in FIG. 20) of the audio management information (AMGI) from the digital information medium (10); audio contents extraction means (30, 50 to 54, 60) for extracting contents (audio cells and the like in FIG. 7) of the audio contents (ATS) on the basis of the contents (ATT_SRP for AOTT in FIG. 20) of the audio management information (AMGI); and video contents extraction means (30, 50 to 54, 58) for extracting contents (video cells in FIG. 8) of the video contents (VTS) on the basis of other contents (ATT_SRP for AVTT in FIG. 20) of the audio management information (AMGI).
The playback apparatus of the second object can play back a digital information medium (AV disc 10) 20 which contains audio data (AOTT_AOB) digitally converted by a predetermined sampling frequency (e.g., 192 kHz) selected from a plurality of different sampling frequencies (48 kHz, 96 kHz, 192 kHz, and the like) and a predetermined number of quantization bits (e.g., 20 bits) selected from a plurality of different numbers of quantization bits (16 bits, 20 bits, 24 bits, and the like), and attribute information (AOTT_AOB_ATR in FIG. 25 included in ATSI in FIG. 24) indicating the predetermined sampling frequency (e.g., 192 kHz) and the predetermined number of quantization bits (e.g., 20 bits) used for this audio data (AOTT_AOB). In this playback apparatus, the management information extraction means (50) detects the predetermined sampling frequency (e.g., 192 kHz) and the predetermined number of quantization bits (e.g., 20 bits) from the attribute information (AOTT_AOB_ATR), and the apparatus further comprises display means (4B) for displaying (the right end on FL display unit 4B in FIG. 30) the detected predetermined sampling frequency (e.g., 192 kHz) and predetermined number of quantization bits (e.g., 20 bits).
In order to achieve the third object, in a recording method according to the present invention, upon recording information on an information recording medium (10) having a volume space (28) including an audio zone (71) and video zone (72) located after the audio zone (71), audio management information (AMG) and audio contents (ATS) are recorded on the audio zone (71), and video management information (VMG) and video contents are recorded on the video zone (72).
In order to achieve the fourth object, in a playback method according to the present invention, upon playing back information from an information recording medium (10) on which an audio zone (71) which records audio management information (AMG) and audio contents (ATS), and a video zone (72) which records video management information (VMG) and video contents (VTS) are recorded, the audio contents (ATS) or video contents (VTS) are accessed on the basis of the audio management information (AMG) to play back their contents, and the video contents are accessed on the basis of the video management information (VMG) to play back their contents.